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1.
Pharmaceutics ; 15(9)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37765212

RESUMO

Tumor hypoxia is considered one of the key causes of the ineffectiveness of various strategies for cancer treatment, and the non-specific effects of chemotherapy drugs on tumor treatment often lead to systemic toxicity. Thus, we designed M1 macrophage-biomimetic-targeted nanoparticles (DOX/CAT@PLGA-M1) which contain oxygen self-supplied enzyme (catalase, CAT) and chemo-therapeutic drug (doxorubicin, DOX). The particle size of DOX/CAT@PLGA-M1 was 202.32 ± 2.27 nm (PDI < 0.3). DOX/CAT@PLGA-M1 exhibited a characteristic core-shell bilayer membrane structure. The CAT activity of DOX/CAT@PLGA-M1 was 1000 (U/mL), which indicated that the formation of NPs did not significantly affect its enzymatic activity. And in vitro drug release showed that the cumulative release rate of DOX/CAT@PLGA-M1 was enhanced from 26.93% to 50.10% in the release medium of hydrogen peroxide, which was attributed to the reaction of CAT in the NPs. DOX/CAT@PLGA-M1 displayed a significantly higher uptake in 4T1 cells, because VCAM-1 in tumor cells interacted with specific integrin (α4 and ß1), and thereby achieved tumor sites. And the tumor volume of the DOX/CAT@PLGA-M1 group was significantly reduced (0.22 cm3), which further proved the active targeting effect of the M1 macrophage membrane. Above all, a novel multifunctional nano-therapy was developed which improved tumor hypoxia and obtained tumor targeting activity.

2.
Molecules ; 27(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36235140

RESUMO

To build a portable and sensitive method for monitoring the concentration of the flavonoid rutin, a new electrochemical sensing procedure was established. By using nitrogen-doped carbonized polymer dots (N-CPDs) anchoring few-layer black phosphorene (N-CPDs@FLBP) 0D-2D heterostructure and gold nanoparticles (AuNPs) as the modifiers, a carbon ionic liquid electrode and a screen-printed electrode (SPE) were used as the substrate electrodes to construct a conventional electrochemical sensor and a portable wireless intelligent electrochemical sensor, respectively. The electrochemical behavior of rutin on the fabricated electrochemical sensors was explored in detail, with the analytical performances investigated. Due to the electroactive groups of rutin, and the specific π-π stacking and cation-π interaction between the nanocomposite with rutin, the electrochemical responses of rutin were greatly enhanced on the AuNPs/N-CPDs@FLBP-modified electrodes. Under the optimal conditions, ultra-sensitive detection of rutin could be realized on AuNPs/N-CPDs@FLBP/SPE with the detection range of 1.0 nmol L-1 to 220.0 µmol L-1 and the detection limit of 0.33 nmol L-1 (S/N = 3). Finally, two kinds of sensors were applied to test the real samples with satisfactory results.


Assuntos
Líquidos Iônicos , Nanopartículas Metálicas , Nanocompostos , Carbono/química , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Nanocompostos/química , Nitrogênio , Polímeros , Rutina/química
3.
Curr Med Chem ; 29(5): 934-956, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34420503

RESUMO

Depression is a common mental illness that belongs to the category of emotional disorders that causes serious damage to the health and life of patients, while inflammation is considered to be one of the important factors that cause depression. In this case, it might be important to explore the possible therapeutic approach by using natural compounds exerting an anti-inflammatory and antidepressant effect, which has not been systematically reviewed recently. Hence, this review aims to systematically sort the literature related to the mechanism of exerting an antidepressant effect through antiinflammatory actions and to summarize the related natural products in the past 20 years in terms of several inflammatory-related pathways (i.e., the protein kinase B (Akt) pathway, monoamine neurotransmitters (5-hydroxytryptamine and norepinephrine) (5-HT and NE), the nod-like receptor protein-3 (NLRP3) inflammasome, proinflammatory cytokines, neurotrophins, or cytokine-signaling pathways), which might provide a useful reference for the potential treatment of depression.


Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR , Estresse Psicológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
4.
Biomater Sci ; 9(9): 3453-3464, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33949434

RESUMO

The application of combination immune-chemotherapy makes up for the limitation of monotherapy and achieves superior antitumor activity against cancer. However, combinational therapy is always restricted by poor tumor targeted drug delivery efficacy. Herein, novel T cell membrane cloaking tumor microenvironment-responsive nanoparticles (PBA modified T cell membrane cloaking hyaluronic acid (HA)-disulfide bond-vitamin E succinate/curcumin, shortened as RCM@T) were developed. T cell membrane cloaking not only serves as a protection shell for sufficient drug delivery but also acts as a programmed cell death-1(PD-1) "antibody" to selectively bind the PD-L1 of tumor cells. When RCM@T is intravenously administrated into the blood stream, it accumulates at tumor sites and responds to an acidic pH to achieve a "membrane escape effect" and expose the HA residues of RCM for tumor targeted drug delivery. RCM accumulates in the cytoplasm via CD44 receptor mediated endocytosis and intracellularly releases antitumor drug in the intracellular redox microenvironment for tumor chemotherapy. T cell membrane debris targets the PD-L1of tumor cells for tumor immunotherapy, which not only directly kills tumor cells, but also improves the CD8+ T cell level and facilitates effector cytokine release. Taken together, the as-constructed RCM@T creates a new way for the rational design of a drug delivery system via the combination of stimuli-responsive drug release, chemotherapeutical agent delivery and cell membrane based immune checkpoint blockade immunotherapy.


Assuntos
Melanoma , Nanopartículas , Membrana Celular , Humanos , Imunoterapia , Microambiente Tumoral
5.
J Colloid Interface Sci ; 581(Pt A): 238-250, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32771735

RESUMO

Hierarchical porous hollow carbon nanospheres (HCNSs) were fabricated directly from raw biomass via a one-step method, in which HCNSs were obtained by thermal treatment of raw biomass in the presence of polytetrafluoroethylene (PTFE). The HCNSs possess coupling merits of uniformly distributed hollow spherical architectures, and high specific surface area, abundant accessible/open micropores and reasonable mesopores, the HCNS-based electrodes deliver high electrochemical capacitance. The formation mechanisms of pores and hollow core-shell structures were explored thoroughly, it is found that the key to the formation of hollow core-shell structure is the onset-pyrolysis temperature difference between raw biomass and PTFE. Moreover, the content of silica had significant effects on the textures of HCNSs, and HCNS with the largest SSA of 1984 m2/g was obtained. Accordingly, a possible mechanism of HCNSs formation was proposed here, where PTFE acted as the pore creation and nucleation agents and raw biomasses were the primary carbon precursors.


Assuntos
Carbono , Nanosferas , Biomassa , Capacitância Elétrica , Porosidade
6.
Front Chem ; 8: 719, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33173759

RESUMO

Metal-organic framework (MOF)-derived nanoporous carbons (NPCs) and porous metal oxide nanostructures or nanocomposites have gathered considerable interest due to their potential use in supercapacitor (SCs) applications, owing to their precise control over porous architectures, pore volumes, and surface area. Bimetallic MOFs could provide rich redox reactions deriving from improved charge transfer between different metal ions, so their supercapacitor performance could be further greatly enhanced. In this study, "One-for-All" strategy is adopted to synthesize both positive and negative electrodes for hybrid asymmetric SCs (ASCs) from a single bimetallic MOF. The bimetallic Zn/Co-MOF with cuboid-like structures were synthesized by a simple method. The MOF-derived nanoporous carbons (NPC) were then obtained by post-heat treatment of the as-synthesized Zn/Co-MOF and rinsing with HCl, and bimetallic oxides (ZnCo2O4) were achieved by sintering the Zn/Co-MOF in air. The as-prepared MOF-derived NPC and bimetallic oxides were utilized as negative and positive materials to assemble hybrid ASCs with 6 M KOH as an electrolyte. Owing to the matchable voltage window and specific capacitance between the negative (NPC) and positive (ZnCo2O4), the as-assembled ASCs delivered high specific capacitance of 94.4 F/g (cell), excellent energy density of 28.6 Wh/kg at a power density of 100 W/kg, and high cycling stability of 87.2% after 5,000 charge-discharge cycles. This strategy is promising in producing high-energy-density electrode materials in supercapacitors.

7.
Nanoscale Res Lett ; 13(1): 342, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30374632

RESUMO

Ni(OH)2 electrocatalysts have acquired lots of research attentions as ideal substitutes for noble metals. However, their electrocatalytic performance still cannot meet the demands for applications due to the difficulties in electron transfer and mass transport. According to kinetics principle, the construction of hollow structure is regarded as an effective method to achieve outstanding electrocatalytic performance. In this work, Ni(OH)2 hollow porous architecture (Ni(OH)2 HPA) was simply synthesized through a coordinating etching and precipitating (CEP) method for the building of enzymatic-free glucose sensors. Ni(OH)2 HPA presents large specific surface area (SSA), ordered diffusion channels, and structure stability. As a detection electrode for glucose, Ni(OH)2 HPA exhibits eminent electroactivity in terms of high sensitivity (1843 µA mM-1 cm-2), lower detection limit (0.23 µM), and short response time (1.4 s). The results demonstrate that Ni(OH)2 HPA has practical applications for construction of enzymatic-free electrochemical sensors. The design of hollow structure also provides an effective engineering method for high-performance sensors.

8.
Nanoscale Res Lett ; 13(1): 218, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30030641

RESUMO

High-performance electrocatalysts for the oxygen reduction reaction (ORR) are essential in electrochemical energy storage and conversion technologies. Fe-N-C electrocatalysts have been developed as one of the most promising alternatives to precious metal materials. Current M-N-C electrocatalysts usually are derived from high-temperature thermal treatment of a nitrogen-containing polymer or metal-organic frameworks (MOFs). Here, we developed Fe-N-C mesoporous nanofibers with low-cost urea and FeCl3 as the nitride and iron source; the electrocatalysts with abundant Fe-Nx active sites and large surface area were synthesized via electrospinning, in situ pyrolysis, and acid treatment process. The use of sealing conditions in the calcination process can effectively improve the nitrogen species content in the catalyst, which is important for improving performance. The as-prepared electrocatalyst material manifests well electrocatalytic performance for ORR in alkaline electrolyte (onset potential of 0.93 V and half-wave potential of 0.82 V); meanwhile, the electrocatalyst expresses good stability and methanol tolerance. This work may provide new thought for developing high-performance ORR electrocatalysts.

9.
Materials (Basel) ; 10(8)2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28825676

RESUMO

Molybdenum (Mo) doped BiVO4 was fabricated via a simple electrospun method. Morphology, structure, chemical states and optical properties of the obtained catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), N2 adsorption-desorption isotherms (BET) and photoluminescence spectrum (PL), respectively. The photocatalytic properties indicate that doping Mo into BiVO4 can enhance the photocatalytic activity and dark adsorption ability. The photocatalytic test suggests that the 1% Mo-BiVO4 shows the best photocatalytic activity, which is about three times higher than pure BiVO4. Meanwhile, 3% Mo-BiVO4 shows stronger dark adsorption than pure BiVO4 and 1% Mo-BiVO4. The enhancement in photocatalytic property should be ascribed to that BiVO4 with small amount of Mo doping could efficiently separate the photogenerated carries and improve the electronic conductivity. The high concentration doping would lead the crystal structure transformation from monoclinic to tetragonal phase, as well as the formation of MoO3 nanoparticles on the BiVO4 surface, which could also act as recombination centers to decrease the photocatalytic activity.

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